It was from frequency analysis lecture and the professor mentioned but I cannot recall.
The K value for English was .067, German was .076. The lowest K was Russian which was .056. When the frequency ...

What do we know about systems that automatically test and grade cipher security. The application in mind would be for checking for compliance with import/export regulations.
I imagine a system that ...

I am currently implementing Salsa20 from the specification as an exercise in learning and self-flagellation.
I have Sections 1-7 passing the test examples provided. I am now stuck on Section 8, The ...

I know Python is a powerful programming language but is it secure for cryptography? I mean is it possible to reverse engineer the program (written in python) and discover the algorithm of cryptography ...

What type of cipher could give ciphertext where for example random ASCII chars between say F-z (symbols and numerals inclusive), but with only a few spaces? Frequency of chars shows some similarities ...

Prove that the affine cipher over Z26 has perfect secrecy if every key is used with equal probability of 1/312.
Just some guidance/help with this problem would be greatly appreciated not sure how to ...

So basically I'm in a class an one problem we were given a while ago was one involving an enigma machine and a few messages. I do not have any idea of how to approach it, and I really need help. The ...

So, I have been assigned an assignment where I had to solve a Vigenere cipher.
Following along with this webpage I managed to get all the way to the chi-squared step. But, that is the problem. Upon ...

Cipher modes typically assume data is streamed or read from a reliable channel with guaranteed ordering. However, many communication transports, such as UDP, are not reliable and don't guarantee order ...

I have to to find the shift value and the message for the following caesar cipher.
OC_VAWDGPM_VHWTVX_VXJOCVZ_GDX_MWO_VWIZVYGWIZ_NODI_
I have already tried it and with the shift value of 21 i get the ...

I have read the Vigenère cipher is secure as long as the key length is the same as the length of the data to be ciphered.
Is this true in cases where the same key is used multiple times.
In that case ...

I need to store a string of digits (0-9) of a fixed size in my database securely.
I've already performed a rainbow table attack on a plain hash, and it broke it in a matter of seconds.
One option I ...

I have a series of integers which I want to convert to random integer (64 bit). The idea here is to produce random numbers very quickly. The issues that good quality random numbers are required with a ...

So the other day, I was piqued by a ciphertext that was trivially encoded through substitution. Solvable only because we can use our eyes to determine word boundary word detection, etc. Trawling the ...

I have the following question about TLS security:
Assume TLS-PSK protected HTTP with AES256-CBC cipher.
When a TLS connection is established, client sends some encrypted data, where the
plaintext is ...

Can anyone comment if the stream cipher described here is safe? The author claims it to be unbreakable, but does not provide any evidence or proof to support this. For completeness, I have reproduced ...

First of all, I know it's a very bad idea to invent your own encryption algorithm. It's better to use existing known, trusted, extensively tested and studied algorithms with a proven track record.
The ...

$A$ has a message that he wants to send to $B$, without a third party being able to learn the contents of the original message.
$A$ encrypts the message and sends it to a server. The server decrypts ...

When implementing a XOR cipher with a pseudo-random key equal in length to the plaintext, Is there a significant difference in potential key strength between keys drawn from a pool of either 1000 or ...